Tort law has always recognized the principle expressed by the Latin
maxim volenti non fit injuria, or "a person is not wronged by that to
which he or she consents." The absence of consent is part of the prima
facie case for tort liability, distinguishing tortious behavior from
socially acceptable behavior. Nevertheless, the value of consumer
choice in strict products liability is surprisingly unclear. Consider
the liability rules governing defects of product design or warning, the
most important categories of product defect. According to the
Restatement (Third) of Torts: Products Liability, "[t]he emphasis is on
creating incentives for manufacturers to achieve optimal levels of
safety in designing and marketing products." The optimal level of
safety has no apparent connection to the amount of safety that would be
chosen by consumers, because "consumer expectations do not play a
determinative role in determining defectiveness." Whether a product is
defective in these cases instead depends on "[a] broad range of
factors," including "the nature and strength of consumer expectations
regarding the product." In some cases, consumer expectations can be
"ultimately determinative" of the liability question, but it is not
apparent why the liability rules exclusively rely on consumer choice in
only these cases but not others. Consumer choice could also limit
liability under the assumed-risk rule, and yet assumption of risk is
not an independent defense in products liability, deepening the
impression that this body of tort law undervalues individual choice.

The impression is misleading. Strict products liability
appropriately values consumer choice. The value of consumer choice,
however, is obscured by the way in which the Restatement (Third) has
de-emphasized the importance of consumer expectations. Properly
understood, the value of consumer choice not only justifies the
liability rules in the Restatement (Third), it also provides the key to
understanding the important limitations of strict products liability,
including those based on assumed risks.